Centering for reinforced-concrete floors and roofs.



A. .IORDAHL.

CENTERING FOR REINFORCED CONCRETE FLOORS AND ROOFS.

APPLICATION FILED NOV. I4. 1914..

l ,2% 1 1 4 Patented Sept. 25, 1917,

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fl%w 6% ANDERS JORDAI-IL, 0F BERLIN, GERMANY.

CENTERING FOR REINFORCED-CONCRETE FLOORS AND ROOFS.

. Specification of Letters Patent.

Patented Sept. 25, 1917.

Application filed November 14, 1914. Serial No. 872,161.

employed for forming the hollow spaces be- 1 tween the beams.

According to my invention the sheet iron molds aredivided longitudinally into two parts, the horizontal legs of which rest on and are lightly attached to easily removable supports under the slab, while the edges of the vertical legs rest on sheeting boards or the like under the beams provided with longitudinal grooves or other means for holding the molds in position. The legs of the molds are preferably of unequal length in order to enable one and the same section to be employed for beams of different height and different distances apart.

To these and other ends my invention consists in the construction. arrangement and combination of parts described hereinafter and pointed out in the claims.

One illustrative embodiment-of my invention and modifications thereof are represented by way of example in the accompanying drawing, wherein Figure 1 is a cross-section through one form of centering according to my invention,

Fig. 2 is a cross-section showing a modification, and

Fig. 3 is a cross-section showing another modified form, in which the distance between the beams of the floor or roof is greater than in the form shown in Fig. 1.

Firstly referring to Fig. 1 the centering comprises scaffolding a which carries she-eting boards or form sections 6 running in th longitudinal direction of the beams. These boards I) are provided with longitudinal grooves or other means for holding the molds into which are inserted the lower edges of L-shaped sheet iron molds or form sections 6, but in the forms shown the grooves or means are located inwardly of the vertical legs of the molds and said grooves open upwardly and have their outer walls sloping outwardly and upwardly, while the inner walls preferably extend substantially vertically. The horizontal legs 'of these molds rest on and are temporarily secured to the supporting boards or form sections 0 running in the longitudinal direction of the beams. These boards 0 are carried by upright supports (Z which rest on and are detachably connected to the scaffolding a.

Each pair of L-shaped mold-sections bearing with their horizontal legs on the same board 0 form an inverted U-section-on which the concrete can be conveniently poured or rammed. The sheet iron molds can be easily removed immediately after the hardening of the thin concrete slab 9 without disturbing the supports 6 of the beams 7. When it is desired to do this, the supports (Z and the boards 0 are removed and the mold sections 0 are tilted downward about their lower edges supported in the grooves in the sheeting boards I), as is indicated in dotted lines in Fig. 1.

As shown in Fig. 1, the legs of the L- shaped mold sections are of uneven length, in order to enable various heights of beams and various distances between the beams to be formed without changing the mold-sections.

As will be understood from Fig. 2 another change in height. can be made by placing on the sheeting boards or form sections 6 distance blocks h which are preferably provided above with sheet-iron clips 2' having a groove corresponding to the groove in the boards or form sections 5. The grooves prevent injury of the possibly not quite hardened-concrete by the edges of the molds e which are engaged in the grooves in the sheeting boards when the same are tilted. This action is due to the fact that the mold sections may swing downwardly and inwardly as shown in dotted lines in Fig. 1, after the center or upright intermediate supports are removed, the sloping walls of the grooves permitting this, while the inner or vertical walls of the grooves in substantially vertical alinement with the opposite walls of the beams bear the weight of the molds until they are removed and limit the displacement of the molds in the opposite directions facing said vertical walls whereby uniformity in the thickness of the beams is insured.

The molds are preferably made in lengths of one to two meters, but they may, of

course, be made shorter or longer. to prevent the concrete adhering to the molds it is preferable to coat them with oilpaint or soap before use. If desired, the molds 6 may be made of any other suitable material.

After the entire centering has been removed the spaces between the ribs may be closed by attaching metal lath or the like under the ribs and afterward plastering same.

The modification shown in Fig. 3 difier from that just described only in that flat sheets Z are arranged on intermediate false work between the L-shaped molds 6, so that the reinforced concrete beams may be at a greater distance apart as is required in ordinary floors or roofs of the type shown.

It is to be understood that the supporting boards a may be made broaderor narrower according to as a greater or smaller distance between the beams is required. Also, the continuous sheeting boards I) may be made broader if it is wished to make a beam of greater thickness.

Having now described my invention what I claim is:

1. In centering for reinforced concrete floors and roofs of the type consisting of beams andslabs the combination with longitudinal members immediately supporting the beams and being provided with longitudinal grooves and a removable upper longitudinal support under the slab, of a pair of L-shaped molds the horizontal legs of which rest on and are attached by means of nails to the said removable support under the slab and the vertical legs of which rest in grooves in the said longitudinal members under the beams, said grooves having inner walls substantially in alinement with the walls of the beams and outer walls permitting downward movement of the molds out of contact with respect to the beams.

52. In centering for reinforced concrete floors and roofs of the type consisting of beams and slabs the combination with longitudinal members. immediately supporting the beams and being provided with longitudinal grooves and a removable upper longitudinal support under the slab, of aipair of L-shaped molds each having legs of unequal length, the horizontal legs of which rest on and are attached to the'said removable support under the slab and the vertical legs of which rest in grooves in the said longitudinal members under the beams, said grooves being located inwardly of or under the vertical faces of the beams whereby the molds may swing downwardly out of contact with any portion of the beams for removal without injuring the same.

3. In centering for reinforced concrete floors and roofs of the type consisting of beams and slabs, the combination withscaf- In order.

same immediately supporting the beams' and being provided with grooves, a removable intermediate support under the slab carried by the scaffolding and a pair of L- shaped molds carried in the grooves or the like of longitudinal members under the beams and by the intermediate supportunder the slab, said grooves having vertical walls toward the beams and outer walls extending therefrom, whereby the molds may be caused to bear against said vertical walls below the beams when displaced from the beams and slabs.

41. In centering fora reinforced concrete floors and. roofs of the type consisting of beams and slabs, the combination with scaffolding; of longitudinal members carried by same immediately supporting the beams and being provided with grooves, a removable intermediate support under the slab carried by the scafiolding, a flat sheet of metal plate carried by the intermediate support and a pairof L-shaped sheet metal molds carried by said plate and resting 'in the grooves of the longitudinal members supporting the beams, said grooves having vertical walls to limit the displacement of the molds toward each other at their portions engaging the grooves but to permit free swinging of the molds in the opposite directions as and for the purposes specified.

5. In a centering for reinforced concrete floors and roofs having beams and slabs, supporting members, spaced and horizontally extending form-sections, a pair of L- shaped form-sections for each of said hori- 'zontal sections, each L-shaped form-section having one leg supported on an opposite longitudinal edge of the horizontal formsection in a vertical position and having the other leg extending laterally in an opposite direction, a removable intermediate form-section supported by said supporting members and having the free ends of the opposing horizontal legs of the L'-shaped form-sections to rest thereupon, and means for normally preventing lateral movement of the vertical legs of the said L-shaped form-sections, but adapted to permit said L-shaped sections to be tipped inwardly away from the beams when the intermediate form-section is removed, whereb the beams will not be injured by the edges of the firstnamed leg portions which rest on the horiing away from the face of the beams and vertical walls located inwardly of the faces 0f the beams 'to permit'displacement of the tened to said removable supports under the slabs and the vertical legs of which rest in grooves to prevent lateral displacement on 15 the said longitudinal members under the beams.

In testimony whereof I have signed my name in the presence of two witnesses.

ANDERS J ORDAHL.

Witnesses CARL KANE, WOLDEMAR HAUPT.

Copies of this patent may be obtained for five cents each, by addressing the commissioner of Patents, Washington, D. G. 

